[No public or meaningful name is available]

Endpoint summary

Description of key information

Due to the lack of defined LC50 values for the majority of the constituents (LC50 higher than the tested doses), it is not possible to quantitatively derive the registered substance’s LC50; however, based on the available data on the constituents, acute hazard from the relevant constituents is not expected and as such the substance does not meet the criteria for the classification as per the CLP regulation.

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records

Reference

Endpoint:

acute toxicity: oral

Data waiving:

other justification

Justification for data waiving:

other:

Endpoint conclusion

Endpoint conclusion:

no study available

Quality of whole database:

Oral study waived. Inhalation route appears to be more relevant.

Acute toxicity: via inhalation route

Link to relevant study records

Reference

Endpoint:

acute toxicity: inhalation

Type of information:

other: Assessment based on available information for constituents

Adequacy of study:

weight of evidence

Study period:

2022

Reliability:

other: Assessment

Rationale for reliability incl. deficiencies:

other: Assessment based on the available information for the constituents.

Principles of method if other than guideline:

An assessment of acute inhalation endpoint of the registered substance was performed based on the information available on the constituents (see attachment for full details).

Test type:

other: Assessment based on the information available for the constituents.

Key result

Remarks on result:

other: It is not possible to quantitatively derive the registered substance’s LC50. However, based on the available data on the constituents, acute hazard from the relevant constituents is not expected and the CLP classification criteria not met.

Interpretation of results:

GHS criteria not met

Conclusions:

Due to the lack of defined LC50 values for the majority of the constituents (LC50 higher than the tested doses), it is not possible to quantitatively derive the registered substance’s LC50. However, based on the available data on the constituents, acute hazard from the relevant constituents is not expected and the registered substance does not meet the criteria for the classification as per the CLP regulation (See attachment for full assessment).

Executive summary:

A constituent-based approach for the read across was applied for the substance.

 

Toxicity data available for the known constituents (except quartz) showed that these constituents did not cause lethality in test animals up to the highest inhalation concentrations tested; however, data on several main constituents come from studies where highest concentrations used were far below the limit concentrations typically suggested by regulatory guidelines; therefore, hazard at higher doses cannot be ruled out. Nonetheless, it is noteworthy that these major constituents in the test substance usually exist in in the powder forms and at the highest testing concentrations which are recommended by regulatory acute inhalation studies (up to 5 mg/L), dry powder aerosols of poorly soluble substances tend to form conglomerates causing physical obstruction of the animals’ airways and impaired respiration and suffocation. Death caused via this mode of action should not be misdiagnosed as toxic effect (see also OECD Guidance #39 on Inhalation Toxicity Studies 2018, section 69). This appears to be the reason why the data available in the literature for these constituents is usually at low concentrations. 

 

For quartz, no acute inhalation toxicity data is available. Silicosis is one of the oldest known occupational diseases. It has only been observed following occupational exposure to respirable crystalline silica and not through exposure to crystalline silica in ambient air. Long term exposure to silica is more relevant because it is potentially carcinogenic and causes progressive, irreversible, fibrotic lung disease. Although acute hazard of quartz is not known, at low concentrations available in the registered substance (~1%), acute toxicity of quartz appears to be even less relevant. For example: low-level crystalline silica exposure on beaches and in ambient air in general, there is no evidence that such low-level exposure causes health effects.

 

Among the unknown constituents (~6%), no one component is present at >1% w/w; hence, they are not relevant for the acute toxicity hazard classification as per the CLP regulation. 

 

In conclusion, due to the lack of defined LC50 values for the majority of the constituents (LC50 higher than the tested doses), it is not possible to quantitatively derive the registered substance’s LC50; however, based on the available data on the constituents, acute hazard from the relevant constituents is not expected and the registered substance does not meet the criteria for the classification as per the CLP regulation.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Physical form:

inhalation: dust

Quality of whole database:

Available information on constituents allows to build a weight of evidence based assessment. See the attached assessment in the endpoint record.

Justification for classification or non-classification

A constituent-based approach for the read across was applied for the substance.

 

Toxicity data available for the known constituents (except quartz) showed that these constituents did not cause lethality in test animals up to the highest inhalation concentrations tested; however, data on several main constituents come from studies where highest concentrations used were far below the limit concentrations typically suggested by regulatory guidelines; therefore, hazard at higher doses cannot be ruled out. Nonetheless, it is noteworthy that these major constituents in the test substance usually exist in in the powder forms and at the highest testing concentrations which are recommended by regulatory acute inhalation studies (up to 5 mg/L), dry powder aerosols of poorly soluble substances tend to form conglomerates causing physical obstruction of the animals’ airways and impaired respiration and suffocation. Death caused via this mode of action should not be misdiagnosed as toxic effect (see also OECD Guidance #39 on Inhalation Toxicity Studies 2018, section 69). This appears to be the reason why the data available in the literature for these constituents is usually at low concentrations. 

 

For quartz, no acute inhalation toxicity data is available. Silicosis is one of the oldest known occupational diseases. It has only been observed following occupational exposure to respirable crystalline silica and not through exposure to crystalline silica in ambient air. Long term exposure to silica is more relevant because it is potentially carcinogenic and causes progressive, irreversible, fibrotic lung disease. Although acute hazard of quartz is not known, at low concentrations available in the registered substance (~1%), acute toxicity of quartz appears to be even less relevant. For example: low-level crystalline silica exposure on beaches and in ambient air in general, there is no evidence that such low-level exposure causes health effects.

 

Among the unknown constituents (~6%), no one component is present at >1% w/w; hence, they are not relevant for the acute toxicity hazard classification as per the CLP regulation. 

 

In conclusion, due to the lack of defined LC50 values for the majority of the constituents (LC50 higher than the tested doses), it is not possible to quantitatively derive the registered substance’s LC50; however, based on the available data on the constituents, acute hazard from the relevant constituents is not expected and the registered substance does not meet the criteria for the classification as per the CLP regulation.